Chinese utility model patent No. 204167438 discloses a heating device of a vehicle Li-ion power battery. The first relay, the heating component and the battery assembly of the device are connected in series to form a heating loop. The heating component is formed by a number of heating film connected in series, and each heating film at the side of a single battery core.
At present, when a Li-ion battery is in the temperature range from 20° C. to 40° C., the charging and discharging performance is the best, and the service life is the longest. However, the battery package on the market basically uses an air cooling manner, meanwhile integrating a solid heater thereon, such as a metal heating film or a PTC plate-type heater. Or, a liquid cooling system is used, which either has no heating function, or needs to be heated by using a heating stick. The application of a battery is limited if there is no heating function. If using a heating stick or heaters of other types, the electric energy of these heaters are all coming from the battery itself, the energy of the battery system would be consumed, which leads to reducing of the cruising distance of electric vehicle when being only electrically powered, and greatly decreasing the effective ratio of the energy used by battery package for cruising distance.
Therefore, it is needed to provide a new battery heating system, to overcome the defect mentioned above.